Ablation planning system

Abstract

An ablation planning system includes a user interface (104) configured to permit selection of inputs for planning an ablation procedure. The user interface is further configured to incorporate selection of ablation probes and one or more combinations of ablation powers, durations or parameters applicable to selected probes in the inputs to size the ablation volumes. The user interface includes a display for rendering internal images of a patient, the display permitting visualizations of the ablation volumes for different entry points on the internal images. An optimization engine (106) is coupled to the user interface to receive the inputs and is configured to output an optimized therapy plan which includes spatial ablation locations and temporal information for ablation so that collateral damage is reduced, coverage area is maximized and critical structures are avoided in a planned target volume.

1 . A microwave ablation planning system, comprising:
 a user interface configured to permit selection of inputs for planning an ablation procedure using multiple ablation probes, the user interface further configured to enable a user to select the multiple ablation probes for the ablation procedure, a location of a skin entry point for each of the selected multiple ablation probes, and one or more combinations of ablation powers, durations, or parameters applicable to the selected multiple ablation probes, wherein the selected inputs determine sizes and shapes of ablation volumes, wherein the user interface further includes a display configured to render internal images of a patient, wherein the display is further configured to display visualizations of the ablation volumes on the internal images;   a database configured to store information related to the multiple ablation probes such that the information is retrievable by the user interface to select the multiple ablation probes to be employed as the inputs, wherein the multiple ablation probes are microwave ablation probes and wherein the stored information includes power and duration information corresponding to a plurality of ablation volume sizes and shapes; and   an optimization engine coupled to the user interface and configured to receive the inputs and configured to output an optimized microwave ablation therapy plan which includes spatial ablation locations and power and duration information such that in a planned microwave ablation target volume collateral damage is reduced, ablation coverage is maximized, and critical structures are avoided.   
     
     
         2 . The system as recited in  claim 1 , wherein the optimization engine computes a cost based on the inputs and minimizes the cost to determine the output optimized microwave ablation therapy plan. 
     
     
         3 . The system as recited in  claim 2 , wherein the optimization engine includes a penalty function to penalize the cost for unwanted effects. 
     
     
         4 . The system as recited in  claim 1 , wherein the inputs include one or more of the planned target volume to be covered in the microwave ablation therapy plan, a margin of error, ablation coverage, collateral damage, regions to be excluded, ablation power, and ablation duration. 
     
     
         5 . The system as recited in  claim 1 , wherein the output includes locations for ablation centers, a minimum number of ablations, a minimum ablation power or duration, predicted ablation metrics, collateral damage, unablated planned target volume regions, and damage to critical structures. 
     
     
         6 . The system as recited in  claim 7 , wherein the plurality of ablation shapes include ellipses, a major axis of each ellipse lying along a trajectory between an ablation volume center and a corresponding skin entry point, radii of each ellipse being controlled by the ablation power and duration. 
     
     
         7 . The system as recited in  claim 1 , wherein the optimization engine is configured to interpolate microwave ablation radii from the power and time data for a plurality of ablation shapes by assuming the ablation radii grow proportionally with increasing ablation duration and increasing ablation power. 
     
     
         8 . A method for planning a microwave ablation procedure, comprising:
 displaying an internal image of a patient on a display of a user interface, wherein the user interface is configured to permit selection of inputs for planning an ablation procedure using multiple ablation probes, the user interface further configured to input a selection of the multiple ablation probes, input a location of a skin entry point for each of the selected multiple ablation probes, and input one or more combinations of ablation power and duration for the selected ablation probes to size ablation volumes, the user interface including a display configured to render internal images of a patient and visualize the ablation volumes, and the skin entry points on the internal images;   wherein the multiple ablation probes are microwave ablation probes, a size of the ablation volume of each of the microwave ablation probes being controlled by application power and duration supplied to each microwave ablation probe;   selecting a plurality of the ablation probes for performing the ablation procedure using the user interface;   selecting a location of the skin entry point for each of the multiple ablation probes on the internal image;   generating an optimized microwave ablation plan which includes spatial ablation locations and ablation power and duration information that reduces collateral damage, maximizes ablation coverage area, and avoids critical structures in a planned target volume; and   outputting the optimized therapy plan.   
     
     
         9 . The method as recited in  claim 8 , wherein generating the optimized microwave plan includes minimizing a cost based on the selected inputs. 
     
     
         10 . The method as recited in  claim 9 , further including computing a penalty function to penalize the cost for an unwanted effect. 
     
     
         11 . The method as recited in  claim 9 , wherein the selected inputs includes one or more of a margin of error, ablation coverage, collateral damage, regions to be excluded, the ablation power, and the ablation duration. 
     
     
         12 . The method as recited in  claim 8 , wherein the optimized microwave ablation plan includes locations for ablation centers, a minimum number of ablations, a minimum ablation power or duration, ablation metrics, collateral damage, unablated planned target volume regions, and damage to critical structures. 
     
     
         13 . The method as recited in  claim 8 , wherein optimizing the microwave ablation plan includes interpolating microwave ablation radii from the power and duration for a plurality of ablation shapes and/or sizes by assuming the ablation radii grow proportionally with increasing duration and increasing power. 
     
     
         14 . The method as recited in  claim 8 , wherein at least one of the microwave ablation probes is configured to generate an ellipsoidal ablation volume, radii of the ellipsoidal ablation volume being proportional to the ablation power and duration, a major axis of the ellipsoidal ablation volume being defined by a trajectory between the ablation volume and the corresponding skin entry point, and wherein optimizing the therapy plan includes adjusting the ablation power and duration and the skin entry points. 
     
     
         15 . A microwave ablation planning system for planning ablations of targets with complex shapes comprising:
 a display configured to render internal images of an internal region of a patient including tissue to be ablated, the display further being configured to visualize a planned target ablation volume to be ablated, ablation volumes of each of a plurality of microwave ablation probes and skin entry points, each skin entry point defining a trajectory from the skin entry point to an ablation center to a corresponding one of the ablation volumes;   a user interface configured to enable selection of at least two of the plurality of microwave ablation probes and to retrieve an ablation duration and power to ablation volume shape relationship for the selected microwave ablation probes;   one or more processors configured to:
 determine a microwave ablation plan which maximizes coverage of the planned target volume and avoids critical structures, the microwave ablation plan including identifiers of the selected at least two of the microwave ablation probes, an entry point corresponding to each identified microwave ablation probe, power applied to each identified microwave ablation probe, and a duration the power is applied to each identified microwave ablation probe. 
   
     
     
         16 . The system as recited in  claim 15 , wherein the one or more processors are further configured to control the display to render the internal images of the internal region of the patient, visualize the planned treatment volume, and visualize the volume ablated by the two or more selected microwave ablation probes pursuant to the microwave ablation plan. 
     
     
         17 . The system as recited in  claim 16 , wherein the user interface is configured to allow a clinician to adjust the entry points, the ablation powers, and the ablation durations. 
     
     
         18 . The system as recited in  claim 15 , wherein the one or more processors is configured to determine the microwave ablation plan using a cost function. 
     
     
         19 . The system as recited in  claim 18 , wherein determining the microwave ablation plan further includes using a penalty function.